HEAT

2004 Hyundai Elantra • 4 cylinder FWD Automatic • 160,000 miles

I Got a Hyundai 2004 Élentra and no heat on idle seepd.
Full prestone change thermostat, Only heat when the engin speed up to 1200 RPM. Is there any valve to bleede de ccoling systeme.
Thanks
Raynald Martel "COOL INSIDE MY CAR"